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951.
Kim YJ Kim JY Cho JW Cha DS Lee MJ Osamu T Kwon HJ Cho KH Lee JH Song CW Jung HS 《Birth defects research. Part B, Developmental and reproductive toxicology》2008,83(2):97-103
BACKGROUND: In this study, the mutated phenotypes were produced by treatment of chemical mutagen, N‐ethyl‐N‐nitrosourea (ENU). We analyzed the mutated mice showing the specific phenotype of ectodermal dysplasia (ED) and examined the affected gene. METHODS: Phenotypes, including size, bone formation, and craniofacial morphology of ENU‐induced ED mice, were focused. Tooth development and expression of several molecules were analyzed by histologic observations and immunohistochemistry. We carried out genome‐wide screening and quantitative real‐time PCR to define the affected and related genes. RESULTS: As examined previously in human ectodermal dysplasia, ENU‐induced ED mice showed the specific morphologic deformities in tooth, hair, and craniofacial growth. Tooth development in the ENU‐induced ED mice ceased at early cap stage. In addition, skeletal staining showed retardation in craniofacial development. Finally, the affected gene, which would be involved in the mechanism of ED, was located between the marker D3Mit14 and D3Mit319 on chromosome 3. CONCLUSIONS: The affected gene in ENU‐induced ED mice showed several defects in ectodermal organogenesis and these results indicate that this gene plays an important role in mouse embryogenesis. Birth Defects Res (Part B) 2008. © 2008 Wiley‐Liss, Inc. 相似文献
952.
Cha YS Ji H Yun DW Ahn BO Lee MC Suh SC Lee CS Ahn EK Jeon YH Jin ID Sohn JK Koh HJ Eun MY 《Molecules and cells》2008,26(2):146-151
The brown planthopper (BPH) is a major insect pest in rice, and damages these plants by sucking phloem-sap and transmitting viral diseases. Many BPH resistance genes have been identified in indica varieties and wild rice accessions, but none has yet been cloned. In the present study we report fine mapping of the region containing the Bph1 locus, which enabled us to perform marker-aided selection (MAS). We used 273 F8 recombinant inbred lines (RILs) derived from a cross between Cheongcheongbyeo, an indica type variety harboring Bph1 from Mudgo, and Hwayeongbyeo, a BPH susceptible japonica variety. By random amplification of polymorphic DNA (RAPD) analysis using 656 random 10-mer primers, three RAPD markers (OPH09, OPA10 and OPA15) linked to Bph1 were identified and converted to SCAR (sequence characterized amplified region) markers. These markers were found to be contained in two BAC clones derived from chromosome 12: OPH09 on OSJNBa0011B18, and both OPA10 and OPA15 on OSJNBa0040E10. By sequence analysis of ten additional BAC clones evenly distributed between OSJNBa0011B18 and OSJNBa0040E10, we developed 15 STS markers. Of these, pBPH4 and pBPH14 flanked Bph1 at distances of 0.2 cM and 0.8 cM, respectively. The STS markers pBPH9, pBPH19, pBPH20, and pBPH21 co-segregated with Bph1. These markers were shown to be very useful for marker-assisted selection (MAS) in breeding populations of 32 F6 RILs from a cross between Andabyeo and IR71190, and 32 F5 RILs from a cross between Andabyeo and Suwon452. 相似文献
953.
Song BC Kim KY Yoon JJ Sim SH Lee K Kim YS Kim YK Cha CJ 《Journal of microbiology and biotechnology》2008,18(3):404-409
The brown-rot basidiomycete Fomitopsis palustris is known to degrade crystalline cellulose (Avicel) and produce three major cellulases, exoglucanases, endoglucanases, and beta- glucosidases. A gene encoding endoglucanase, designated as cel12, was cloned from total RNA prepared from F. palustris grown at the expense of Avicel. The gene encoding Cel12 has an open reading frame of 732 bp, encoding a putative protein of 244 amino acid residues with a putative signal peptide residing at the first 18 amino acid residues of the N-terminus of the protein. Sequence analysis of Cel12 identified three consensus regions, which are highly conserved among fungal cellulases belonging to GH family 12. However, a cellulose-binding domain was not found in Cel12, like other GH family 12 fungal cellulases. Northern blot analysis showed a dramatic increase of cel12 mRNA levels in F. palustris cells cultivated on Avicel from the early to late stages of growth and the maintenance of a high level of expression in the late stage, suggesting that Cel12 takes a significant part in endoglucanase activity throughout the growth of F. palustris. Adventitious expression of cel12 in the yeast Pichia pastoris successfully produced the recombinant protein that exhibited endoglucanase activity with carboxymethyl cellulose, but not with crystalline cellulose, suggesting that the enzyme is not a processive endoglucanase unlike two other endoglucanases previously identified in F. palustris. 相似文献
954.
Anni 2.0 is an online tool () to aid the biomedical researcher with a broad range of information needs. Anni provides an ontology-based interface to MEDLINE
and retrieves documents and associations for several classes of biomedical concepts, including genes, drugs and diseases,
with established text-mining technology. In this article we illustrate Anni's usability by applying the tool to two use cases:
interpretation of a set of differentially expressed genes, and literature-based knowledge discovery. 相似文献
955.
Autophagy has been reported to be increased in irradiated cancer cells resistant to various apoptotic stimuli. We therefore hypothesized that induction of autophagy via mTOR inhibition could enhance radiosensitization in apoptosis-inhibited H460 lung cancer cells in vitro and in a lung cancer xenograft model. To test this hypothesis, combinations of Z-DEVD (caspase-3 inhibitor), RAD001 (mTOR inhibitor) and irradiation were tested in cell and mouse models. The combination of Z-DEVD and RAD001 more potently radiosensitized H460 cells than individual treatment alone. The enhancement in radiation response was not only evident in clonogenic survival assays, but also was demonstrated through markedly reduced tumor growth, cellular proliferation (Ki67 staining), apoptosis (TUNEL staining) and angiogenesis (vWF staining) in vivo. Additionally, upregulation of autophagy as measured by increased GFP-LC3-tagged autophagosome formation accompanied the noted radiosensitization in vitro and in vivo. The greatest induction of autophagy and associated radiation toxicity was exhibited in the tri-modality treatment group. Autophagy marker, LC-3-II, was reduced by 3-methyladenine (3-MA), a known inhibitor of autophagy, but further increased by the addition of lysosomal protease inhibitors (pepstatin A and E64d), demonstrating that there is autophagic induction through type III PI3 kinase during the combined therapy. Knocking down of ATG5 and beclin-1, two essential autophagic molecules, resulted in radiation resistance of lung cancer cells. Our report suggests that combined inhibition of apoptosis and mTOR during radiotherapy is a potential therapeutic strategy to enhance radiation therapy in patients with non-small cell lung cancer. 相似文献
956.
957.
M Lundervold EJ Milner-Gulland CJ O'Callaghan C Hamblin A Corteyn AP Macmillan 《Acta veterinaria Scandinavica》2004,45(4):211-224
The results of a serological survey of livestock in Kazakhstan, carried out in 1997–1998, are reported. Serum samples from
958 animals (cattle, sheep and goats) were tested for antibodies to foot and mouth disease (FMD), bluetongue (BT), epizootic
haemorrhagic disease (EHD), rinderpest (RP) and peste des petits ruminants (PPR) viruses, and to Brucella spp. We also investigated the vaccination status of livestock and related this to changes in veterinary provision since independence
in 1991. For the 2 diseases under official surveillance (FMD and brucellosis) our results were similar to official data, although
we found significantly higher brucellosis levels in 2 districts and widespread ignorance about FMD vaccination status. The
seroprevalence for BT virus was 23%, and seropositive animals were widespread suggesting endemicity, despite the disease not
having being previously reported. We found a few seropositives for EHDV and PPRV, which may suggest that these diseases are
also present in Kazakhstan. An hierarchical model showed that seroprevalence to FMD and BT viruses were clustered at the farm/village
level, rather than at a larger spatial scale. This was unexpected for FMD, which is subject to vaccination policies which
vary at the raion (county) level. 相似文献
958.
Karetnikova EA Chaĭkovskaia ON Sokolova IV Nikitina LI 《Prikladnaia biokhimiia i mikrobiologiia》2008,44(5):545-553
Sequential photo- and biodegradation of p-cresol was studied using a mercury lamp, as well as KrCl and XeCl excilamps. Preirradiation of p-cresol at a concentration of 10(-4) M did not affect the rate of its subsequent biodegradation. An increase in the concentration of p-cresol to 10(-3) M and in the duration preliminary UV irradiation inhibited subsequent biodegradation. Biodegradation of p-cresol was accompanied by the formation of a product with a fluorescence maximum at 365 nm (lambdaex 280 nm), and photodegradation yielded a compound fluorescing at 400 nm (lambdaex 330 nm). Sequential UV and biodegradation led to the appearance of bands in the fluorescence spectra that were ascribed to p-cresol and its photolysis products. It was shown that sequential use of biological and photochemical degradation results in degradation of not only the initial toxicant but also the metabolites formed during its biodegradation. 相似文献
959.
Minho Cha Eun Jung Kim Jihyang Park Juhan Kim Byung-Gee Kim 《Enzyme and microbial technology》2008,43(7):480-485
Various yeast strains were examined for the microbial reduction of ethyl-3-oxo-3-phenylpropanoate (OPPE) to ethyl-(S)-3-hydroxy-3-phenylpropanoate (S-HPPE), which is the chiral intermediate for the synthesis of a serotonin uptake inhibitor, Fluoxetine. Kluyveromyces lactis KCTC 7133 was found as the most efficient strain in terms of high yield (83% at 50 mM) and high optical purity ee > 99% of S-HPPE. Based on the protein purification, activity analysis and the genomic analysis, a fatty acid synthase (FAS) was identified as the responsible β-ketoreductase. To increase the productivity, a recombinant Pichia pastoris GS115 over-expressing FAS2 (α-subunit of FAS) of K. lactis KCTC7133 was constructed. In the optimized media condition, the recombinant P. pastoris functionally over-expressed the FAS2. Recombinant P. pastoris showed 2.3-fold higher reductase activity compared with wild type P. pastoris. With the recombinant P. pastoris, the 91% yield of S-HPPE was achieved at 50 mM OPPE maintaining the high optical purity of the product (ee > 99%). 相似文献
960.
Cha K Hong HW Choi YG Lee MJ Park JH Chae HK Ryu G Myung H 《Biotechnology letters》2008,30(11):1893-1899
Mice were fed either 13 nm silver nanoparticles or 2–3.5 μm silver microparticles. The livers were then obtained after 3 days
and subjected to a histopathological analysis. The nanoparticle-fed and microparticle-fed livers both exhibited lymphocyte
infiltration in the histopathological analysis, suggesting the induction of inflammation. In vitro, a human hepatoma cell
line (Huh-7) was treated with the same silver nanoparticles and microparticles. The mitochondrial activity and glutathione
production were hardly affected. However, the DNA contents decreased 15% in the nanoparticle-treated cells and 10% in the
microparticle-treated cell, suggesting a more potent induction of apoptosis by the nanoparticles. From a microarray analysis
of the RNA from the livers of the nano- and micro-particle-fed mice, the expression of genes related to apoptosis and inflammation
was found to be altered. These gene expression changes in the nanoparticle-treated livers lead to phenotypical changes, reflecting
increased apoptosis and inflammation. The changes in the gene expression were confirmed by using a semi-quantitative RT-PCR. 相似文献